Ergonomics ; Humans ; Occupational Health

Objective To construct a lentiviral expression vector of murine RelB for RNAi,and then to effectively silence the RelB gene expression of murine bone marrow derived dendritic cells for constructing the bone marrow tolerogenic dendritic cell,in order to provide an experimental foundation for a novel clinical therapy of autoimmune disease.Methods RelB shRNA sequence of mouse was designed by on-line designer software on Corp.Invitrogen,after synthesis and annealing,double strand oligonucleotides(dsoligoes)were cloned into the pENTRTM/U6 plasmid,then after sequencing,a positive clone was further subcloned into pLenti6/BLOCK-iTTM-DEST vector.It was then transformed into stb13 competent cell,and after sequencing,293FT cell line was transfected by above positive recombined plasmid and lentiviral packing materials.It was incubated for 48 to 72 h in a 37℃,5% CO2 incubator.Culture supernatant was harvested and stored at-80℃,then the virus titer was determined by serial dilution assay.Results It was showed from sequencing figures that all the pENTRTM/U6-RelB-shRNA plasmids were positive clone vector,and this positive recombinant vector was recombined with pLenti6/BLOCK-iTTM/U6-DEST vector.It was then transformed into stb13 competent cell and screen positive clone by ampicillin,and resequenced by the use of primer forward U6 primer.The results also showed that recombinant lentiviral vector was positive clone.Viral particle was packaged with other packaging material mediated by lipofectamine 2000 in 293FT cell line.Cultural supernatant was collected and stored at-80℃,and lentiviral particle titer was determined by serial dilution assay with 6?105/transduced unit.Conclusion Lentiviral shRNA expression vector of murine RelB gene for RNAi was successfully constructed.It might be a rational procedure to make tolerogenic DC,and then to develop a DC vaccine and DC-based immunotherapy for autoimmune diseases.

Objective To explore the changes and clinical significance of plasma tissue factor pathway (TFP) levels during the onset of acute ischemic cardiac and cerebral vessel disease. Methods The study population consisted of 69 patients with AMI and 71 with AICS as well as 50 age-matched healthy volunteers. Blood samples were obtained during the onset period of AMI and AICS. Tissue factor (TF) and tissue factor pathway inhibitor (TFPI) activity in plasma were assayed with the chromogenic assay, Plasma TF and TFPI antigen were measured with ELISA, Plasma FⅦ coagulation activity (FⅦ:C) was developed in the one- stage system. Plasma FⅦa was determined by soluble TF assay, plasma prothrombin (FII) and fibrinogen (Fbg) were measured by one-stage amidolytic assay and thrombin time (TT) respectively. Results In the AMI group, compared with the control group, plasma TF activities and antigens, TFPI activities and antigens as well as FⅦa were significantly higher(all P0.05), plasma FII and Fbg were also remarkably increased (both P0.05). Conclusion The initiation of TF pathway would be associated with the onset of AMI and AIS, but the changes of TF, TFPI, FⅦ:C and Fbg in AMI are different from those in AICS, endothelial dysfunction and the blood is in hypercoagulable state.

Objective To study the biological effects of nucleic transcript factor NF-?B/RelB gene silencing on bone marrow derived dendritic cells(BMDCs).Methods For constructing a new type of DCs,RNAi RelB DC,mouse BMDCs were cultured through IL-4 and GM-CSF cytokine inducing system and were purified with CD11c positive immunomicrobeads by flow cytometer,and RelB gene was silenced with PCR expression cassettes.The RelB RNA interference effect in DCs was proved at both mRNA and protein levels.The biological characteristics of RNAi RelB DCs were investigated by means of cell morphology,cell surface markers and mixed lymphocyte reaction ability.The cell microstructure was observed using scanning electron microscopy and transmission electron microscopy.The cell surface markers,such as MHC-Ⅱ,CD86 and CD40,were detected by flow cytometer.The mixed lymphocyte reaction ability,as well as the ability of DCs in stimulating allogeneic T cells proliferation,was detected by 3H-TdR incorporation method.Results RNAi RelB DCs seemed to have fewer and shorter spikes and many folds under scanning electron microscopy.Many phagocytic vacuoles were observed in the cytoplasm under transmission electron microscopy.DCs surface molecules,MHC-Ⅱ,CD86 and CD40,were expressed at a relatively lower level compared with the control DCs.This RNAi RelB DCs also showed weak allogeneic T cells stimulating ability in vitro in MLR.Conclusion The dendritic cells derived from bone marrow are characterized the biological features and immunological function of immature DC with silencing of RelB gene.This kind of RNAi RelB DCs may be used to induce immunotolerance as a novel tolerogenic DCs.

Along with the development of modern biological technology, the adversity of the transgenic products has aroused increasing attention. The origin of biosafety issues, the safety of genetically modified organisms and its impact on the ecological environment and human health were introduced in this paper. Here, the safety issues of the leakage of laboratory recombinant gene fragments were discussed also, finally, the focuses on biosafety and preventive measures were reviewed.

To design and manufacture a new bone matrix material (NBM) composed of both organic and inorganic materials for bone tissue engineering, the osteogenic potential of NBM combined with osteoblasts was studied in vitro and in vivo. Osteoblasts from bone marrow stromal cells of New Zealand rabbit were cultured with NBM in vitro , then the materials combined with osteoblasts were implanted into the skeletal muscles of rabbits. The osteogenic potential of NBM was evaluated using contrast microscope, scan electromicroscope and histological examination. Osteoblasts could attach and proliferate well in the NBM, secrecting lots of extracellular matrix, while in vivo experiment of the NBM in osteoblasts group showed that a large number of lymphacytes and phagocytes invaded into the inner of the material in the rabbit skeletal muscle beds after 4 weeks of implantation, no new bone formation was observed after 8 weeks. The different osteogenic potential expressed by NBM between in vitro and in vivo may be due to the immunogenity of NBM which causes cellular immunoreaction to destroy the osteogenic environment. More attention should be paid to the immunoreaction problem in tissue engineering between the host and organic inorganic composite materials.

Hematopoietic stem/progenitor cells have the potential of self-renewal,proliferation and multidirectional differentiation,which maintain the normal haematopoiesis of bnmml body.Alterations in the number and function of mature blood cells in the peripheral blood commonly observed in humans exposed to microgravity (μ-g)are results of many reasons.The change of biological characteristic of hematopoietic stem/progenitor cells is one of the important ressons.Migration,proliferation,and differentiation of hematopoietic stem/progenitor cells under microgravity are summarized in this article.

MicroRNAs (miRNAs) are evolutionarily conserved small noncoding RNAs of-22 nucleotides that exist in a wide variety of organisms,including animals,plants and virus.Mature miRNAs are able to control gene expression at a post-transcriptional level,either by blocking mRNA translation or inducing their degradation.Hepatitis B virus X protein (HBX) is a 17000 protein that is implicated to play a crucial role in hepatocarcinogenesis.Recently,many studies have shown that HBX is associated with miRNA regulation,and is involved in regulating fundamental biological processes of tumor in cell proliferation,differentiation and apoptosis.

The change of gravity causes a series of physiological dysfunctions,such as redistribution of blood,destruction of skeleton,reduction of hemopoietic tissue and so on.Since the success of mission to the moon and construction of space station,the study on change of human physiological functions under microgravity has been underway.With the machine of microgravity developing maturely,associated researches have made big steps forward.However,intensive study on the changes of human hemostasis and thrombosis under the microgravity are still needed,especially in the area of high incidences of bleeding and thrombotic diseases.The result will help to prevent hemostasis and thrombosis on astronaut and promote the development of our national aerospace industry.

The article presented the drugs supply management mode reform in place since 2009 in the one district of Shanghai.Authors analyzed and commented the implementation and outcomes,and studied the potentials of successful promotion nationwide.They hold that such a mode works to some extent in terms of reducing management costs of medical institutions,lowering drug purchase price,encouraging rational drug use of such institutions,and reforming the compensation manner for medical institutions.This mode,however,calls for an operating environment in need of not only funding support,but also new concepts and economic development strength of the society as a whole.This means that such a mode is only recommended in developed areas in China.